We get asked this question many times, so I thought it might be wise to post this. Yes, every now and again Joe Iso-Tip has a good idea. So here’s the difference between our soldering irons to help determine the one for you…
First of all, the 7000 series irons (7700,7800,7904) can use any of the tips; they are all interchangeable. That said, they all heat up quickly…very quickly. In fact, it’s around 10 seconds. You move the red dial on all of them to unlock and push the button. The light will shine on your solder joint and remain on until you have the heat you want, then release the button. Press again for more heat.
All models work the same and very simple to operate. I have to caution you at this point because everyone who gets our iron thinks I’m kidding. They get an iron, hold the button down for 3 to 4 seconds, and then touch it to their finger. Shortly thereafter they yell, “Boy! That was stupid!” They learn the hard way that the iron heats up fast. I should make a video of this because everyone does it, and yes, it’s funny to watch. I always say “What? Did you think I was kidding?” Now we all know the tips are interchangeable between irons.
The 7700 is the basic unit and the biggest seller for good reason. It’s like the difference between electric and crank up windows in your car. Windows aren’t that hard to crank and when a motor or switch goes out in electric ones, it becomes costly and a real pain to deal with. The 7700 is the crank up window version of our soldering irons. The people that use them will use words like dependable, bullet-proof, and easy, since it’s simple to change the battery. The 7800 is the same iron as the 7700 but with a quick-charge mode added. The 7700 and 7800 will both perform roughly 125 solder joints on a circuit board. I know that number is a hard thing to determine, but we had to come up with something. If you put a heat sink on the tip, and hold the button down continuously, it will stay at max heat for about 20 minutes solid. Most people use it for a few joints, pop it back in the charger, and it keeps on tickin’. If your battery goes down and you need it charged quickly, the 7800 has a white slide button on the side. Sliding that down will put the iron in quick-charge mode. From a dead state, it will charge in about 60 minutes. The 7700 will take 4 hours from dead. The way we accomplish that is neat, but again, it’s like electric car windows. The majority of people who want a battery replaced in the 7800 send it in to us for a complete rebuild of the iron and charger.
Oh! I forgot to mention that WE REBUILD OLD IRONS. The 7904 Iron is the same as the 7700 except it is longer in length due to it having a larger battery which will do roughly twice the number of solder joints per charge. The 7904 has no quick charge feature, which means it takes 4 hours from dead to charge, same as the 7700.